Acylglycerol synthesis in liver of type II diabetic rats fed a diet supplemented with either n-6 or n-3 fatty acids.

Liver is one of the tissues most actively involved in triacylglycerol synthesis and secretion. Hypertriglyceridemia is commonly associated with the diabetic state which has been detected in very young rats after the induction of experimental diabetes. In the present work, acylglycerol synthesis in liver of streptozotocin-treated rats, fed a diet supplemented with n-3 and n-6 fatty acids, was studied. At the onset of the experiment, plasma triacylglycerol levels increased significantly in diabetic animals when compared to controls. Two weeks after the dietary treatment, the aforementioned parameter decreased in diabetic animals consuming either n-6 or n-3 fatty acids. In control rats, n-3 fatty acids depressed triacylglycerol synthesis in liver microsomes. In the diabetic group both diets increased diacylglycerol and triacylglycerol synthesis. The addition of liver cytosolic fraction from control rats to the incubation medium, stimulated the triacylglycerol synthesis in all the groups. Nevertheless, the radioactivity recovered in the neutral lipid fractions was lower in the samples from rats fed n-3 fatty acids compared to n-6. We conclude that dietary n-3 fatty acids decreased significantly triacylglycerol plasma levels in diabetic rats probably through the inhibition of liver triacylglycerol secretion. In addition, there probably is an n-3 fatty acid sensitive factor in the liver cytosolic fraction able to depress triglyceride synthesis.